It’s not quite the Fountain of Youth, but it may be the river that leads to it. In a paper published in the journal Lancet Oncology, scientists found that a small group of men who made changes in the way they ate and handled their emotional needs showed longer telomeres in their cells.

That’s exciting because previous research suggested that telomeres, which are protein and DNA-based complexes that cap the ends of chromosomes, regulate the aging of cells. Each time a cell divides, a section of telomeres erodes, and, like a burning candle wick, when telomeres are exhausted, so is the life of the cell.

In the latest study, the scientists, led by Dr. Dean Ornish, of the Preventive Medicine Research Institute and University of California San Francisco, who is known for promoting a low-fat diet – a really low-fat one that includes only 10% of a day’s calories from fat – followed 35 men diagnosed with prostate cancer who agreed to have their chromosomes scrutinized over a period of five years. Ornish’s team recruited the men beginning in 2003, for a study looking at whether changing lifestyle behaviors alone could influence progression of their cancer. Some of the men made comprehensive lifestyle changes that included diet, exercise and stress management, while the remainder continued with their existing diet and physical activity plans. In 2005, the group reported that the men who ate a plant-based, low-fat diet high in whole grains, exercised at a moderate intensity for 30 minutes a day, six days a week, took stress management classes including yoga stretching or meditation, and participated in support groups, were less likely to have prostate tumors that progressed compared to the men who weren’t assigned to the program.

At the time, the team also found that the men making the four major lifestyle changes showed higher levels of telomerase in their cells; telomerase is the enzyme that counteracts telomere shortening each time a cell divides. That finding prompted the current study – to see if the higher levels of telomerase contributed to longer telomeres, which has been associated with longer-lived cells.

Indeed, Ornish found that the men who adopted the lifestyle changes increased their telomere length by 10% over five years, compared to a 3% extension among the control group.

“It’s the first controlled study showing that any intervention – in this case lifestyle changes – can increase telomere length, and begin to reverse aging at the cellular level,” says Ornish.

Whether the men will end up adding years to their lives, however, isn’t clear – yet. More research needs to be done to understand why their telomeres lengthened, and whether their cellular extension translates to life extension. But studies of human cell cultures found that those with longer telomeres were able to continue dividing for longer periods of time, raising the hope that telomere lengthening could be one, if not the major contributor to longevity.

It’s also not obvious how the lifestyle changes contributed to longer telomeres – was one more influential than another, or was there some synergistic effect that was more powerful than any of the four changes – in diet, exercise, stress management and social support – alone?

Ornish says it’s likely some combination of the four modifications that is exerting the potent effect on cells; making changes in what you eat and how physically active you are, for example, is challenging, but studies found that those who take advantage of social support networks such as online chat groups or in-person group sessions, tend to be more motivated and compliant with their changes. Similarly, in the study, what began as a support group to help the men stick with their diet or find the right running shoes turned into a deeper source of inspiration and support for the participants. “The groups became intentional communities where the men felt safe enough to let down their emotional defenses and talk authentically and feel safe,” says Ornish.

And in some cases, the sessions helped the men to address why they overate, or preferred to stay at home on the couch, or felt so frustrated over their personal or professional situations. Recognizing and handling this unmet emotional need turned out to be an important way of reducing stress and removing some of the barriers that the participants had to living in a healthier way.

And the fact that the more faithfully the men who made the lifestyle changes adhered to their plant-based diet, their exercise regimen, their stress management techniques and support group schedule, the longer their telomeres were, suggests that the effect is not only real, but sustainable. “The more you change, the more you improve at any age,” says Ornish. “It’s not all-or-nothing, and that’s a profoundly empowering message to give to people.”

One mystery that Ornish and his group hope to resolve – or hope others will also investigate – is the fact that despite their longer telomeres, the men who made lifestyle changes did not show higher levels of telomerase. It’s possible that the enzyme is active in initially lengthening telomeres, and drops off as the telomeres get longer, or that there are other, non-telomerase-based ways to lengthen the ends of chromosomes.

Even as other scientists verify and delve deeper in how the lifestyle changes contributed to the longer telomeres, Ornish says the face that the intervention involved no medication, no surgery and only behavior changes, should be encouraging to anyone hoping to hold off aging for as long as possible. “We tend to think of advances in medicine as something high tech and expensive like a new drug or a new device,” he says. “What we were able to show using high tech state-of-the-art scientific measures was how powerful simple, low-tech interventions can be.”